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Chan
12-31-2011, 03:00 PM
Bronze fastenings in epoxy encapsulated boats are a waste of money and natural resources.

thedutchtouch
12-31-2011, 03:22 PM
ok thanks for your opinion, i don't know enough to disagree but i'm sure someone'll be along shortly

outofthenorm
12-31-2011, 05:00 PM
Everyone is entitled to an opinion, but I tend to react badly when opinion is stated as fact.

- N

rbgarr
12-31-2011, 06:22 PM
It's merely an assertion at this point. It could be worthy of being considered a fact if substantiated by testable evidence. It could be equally asserted that all boats, except for those commercially engaged, are wastes of resources (by definition) as luxuries and indulgences.

hanleyclifford
12-31-2011, 06:40 PM
In light of present cost of bronze the OP may have a point. However, in the event of a breach in the encapsulation the bronze will fare better than the stainless.

David G
12-31-2011, 06:45 PM
Chan,

For epoxy encapsulated boats... I wonder what type of fasteners you prefer.

Jay Greer
12-31-2011, 10:28 PM
Epoxy encapsualted wooden boats are, in general, a waste of time and energy as they are prone to self destruct.
Jay

John How
01-01-2012, 12:29 AM
What does encapsulation have to do with fastening?

Full Tilt
01-01-2012, 02:25 AM
A poorly built boat is a waste of money and natural resources. So is an ugly one.

wizbang 13
01-01-2012, 10:43 AM
I used the theory that the extra moneyspent on epoxy made the galv nails and screws more credible.
And it has worked so far, coming up on 30 years.
If I had the money at the time of building, I would have wasted lots of bronze and monel on her, if for nothing more than re sale value. Maybe my compass would be less screwey too. Compass, what a waste. All the stupid money spent on liferaft/ re packing, Epirbs, and don't get me started on insurance.

David G
01-01-2012, 11:03 AM
Chan,

For epoxy encapsulated boats... I wonder what type of fasteners you prefer.

Chan? Were you going to answer?

Bob Cleek
01-01-2012, 03:20 PM
Epoxy encapsualted wooden boats are, in general, a waste of time and energy as they are prone to self destruct.
Jay

Damn! Jay beat me to it.

I wholeheartedly agree. There is no such thing as an epoxy "encapsulated" boat, but there are certainly a lot of boats built by misinformed people who believe googe slathered all over them is going to change the inherent nature of wood. If you want to "encapsulate" your boat, build it in a bottle.

P.T. Barnum was right, "There's a sucker born every minute." To that, I'd add, "And a troll born every five minutes."

Bob Smalser
01-01-2012, 06:21 PM
... but there are certainly a lot of boats built by misinformed people who believe googe slathered all over them is going to change the inherent nature of wood.

Nature of wood? Don't forget the nature of metal.

Wonder how long it will be before the fasteners work a bit and the epoxy begins to delam from them, letting water in at a faster rate than it can exit through the epoxy during the natural wetting-drying cycle? Add that to the typical cumulative wood damage caused by fasteners through condensation caused by seasonal temperature and humidity changes on wood fibers already a bit damaged by drilling and driving, and you have a perfect recipe for a short life.

However if the builder is sufficiently astute to countersink and bung his fasteners before laying glass and epoxy, then he only has to worry about crevise corrosion caused by the anaerobic environment if he uses stainless steel, and the natural acids in the wood attacking the zinc (followed quickly by salt and moisture) if he uses galvanized steel.

http://1.bp.blogspot.com/-xwz_pasH0Yg/TpJt0A0mH9I/AAAAAAAAASo/LriERwk8mxk/s1600/IMG_2094.JPG

http://pic20.picturetrail.com/VOL12/1104763/9745605/397619693.jpg

Either way, we are back to bronze or monel if much more than 10 years of life is expected in salt water, or 20 in fresh.

Jay Greer
01-01-2012, 06:23 PM
Well Bob Cleek, I have to agree with you. Some where along the process of learning to build a wooden boat, those who are blessed with certain instincts, are enlightened with common sense. I believe it was once said by Alexander Pope that "a little knowledge is a dangerous thing!" In my own humble opinion, it takes a heap of experience with both failure and success to understand the idiosycracies of wooden boat construction. Usually those who believe they have found a new wonder method or material are neophyts to the trade. But, I must always take my own philosophy with a grain of salt and remember the philosophy of Thomas Colin Ratsey who favored the Biblical quote: "Quench not the smoking flax." Which is to say, don't take pleasure in stomping on somone else's dream. Especially those of the youth. Oops, someone is kicking at my soap box! I think it is Bob Smalser, a man who is blessed with an extrordinary amount of common sense!
Jay

Garret
01-01-2012, 06:42 PM
I used the theory that the extra moneyspent on epoxy made the galv nails and screws more credible.
And it has worked so far, coming up on 30 years.
If I had the money at the time of building, I would have wasted lots of bronze and monel on her, if for nothing more than re sale value. Maybe my compass would be less screwey too. Compass, what a waste. All the stupid money spent on liferaft/ re packing, Epirbs, and don't get me started on insurance.

I see your point, but would like to offer a different perspective if I may. I realize that we're talking encapsulated here, but like others far more experienced than I, I'm not sure there is such a thing. For 10 years? Sure. 30+, don't think so.

Neoga is 70 years old. She was built of oak, DF & AYC, all held together with iron or galvanized iron fastenings (hard to tell which now). With the exception of wrought or ductile iron keelbolts, the iron has been the source of most all the gal's problems. Where iron bolts attached oak frames to AYC floors, I can disassemble the frames & remove the floors with one hand - aka compost. Get 3-6" away from the iron & the wood is solid & like new.

The keelbolts were encased in tar, which I think helped them. Since it's a cast iron keel, iron was the only choice & I've replace them with ductile iron - in tar.

Norm Blanchard (her builder) commented in his book that they built boats with iron fastenings because they never expected them to last more than 20 years - so why spend the $ on bronze?

I'll toss out the opinion that when building a boat to be proud of, bronze is worth it. That being said, if it's use iron or don't build it, I guess I'd go with iron....

wizbang 13
01-01-2012, 07:51 PM
My Venus IS 28 years old, over 7000 galv nails and screws.
The only rust is from exposed things like rudder fitters, eye bolts on deck,stuff like that.
Encapsulation is working for me.

Sayla
01-01-2012, 08:21 PM
I'm sticking with bronze -
Even the average humidity here is 40%, let alone if I splash some water around some stressed areas

- I don't see it as a major expense, and as far as resources go: bring it on
- the more people use it, the more people will make it - there seems to be a culture of SS here, and it's not even 316 - and surely it takes more resources to make it than melting copper & silicon

sayla

ramillett
01-02-2012, 03:26 AM
We pulled 100's of 57 year old copper rivets out of Olinka , they were green , but still there :)

http://i697.photobucket.com/albums/vv332/ramillett/millett/P1010107.jpg

Cogeniac
01-02-2012, 09:23 AM
My boat is a combination of iron and bronze. It is not encapsulated, which is why she is in fine shape at, now, 83 years of age.

The iron is in generally better shape than I had imagined. The bolts are pretty wasted however, and where there was some oxygen, like in the bilges, the iron is long gone. I was scraping and painting bilges in prep for the new engine and found one floor that I could rock fore and aft with my hand. So that bolt/drift is dust... All of the iron screws used to hold the frames to the keel during construction are also dust, and are now slowly damaging the frame heels. I'll be drilling those out and plugging the frame ends, and then replacing the frame to floor bolts with bronze.

Where we are replacing parts, we are going with bronze. Screws, bolts and drifts.

We pulled some stainless bolts from the keel cooler, that looked pretty much like the ones in Bob Smalser's post above. The crevice corrosion was so perfectly exemplary, the shipwright gave them to a friend to use in a surveying class.

Boats live in the water, and where they are not wet, they are at leas often damp. If you know how certain metals react in this environment, then one would think you would be able to make a pretty simple informed choice about fasteners. I agree with Garret that if you can't build with bronze then build with iron, but, then if iron vs bronze makes tha much difference, then maybe you should put the project off for a year and save for the bronze...

There may be some inner wisdom from the now, apparently AWOL Chan. If you want to be certain the boat will stay fastened over a long time (>25 years, say) then use bronze, but if you are encapsulating it, it is unlikely to last that long, so use whatever you want. I am sticking with bronze, however...

Garret
01-02-2012, 09:28 AM
Boats live in the water, and where they are not wet, they are at leas often damp. If you know how certain metals react in this environment, then one would think you would be able to make a pretty simple informed choice about fasteners. I agree with Garret that if you can't build with bronze then build with iron, but, then if iron vs bronze makes tha much difference, then maybe you should put the project off for a year and save for the bronze...

Or maybe 2..... Depending on the size of the boat of course. I am refastening everything below the waterline & the screws for doing so will be well over $2,000. Ouch! 5 years ago, it would've been 1/4 that.

Now, if we could go with distributed generation for electricity & start mining all the zillions of miles of copper electric cable.... Guess that's a topic for another thread though. ;)

Mad Scientist
01-02-2012, 01:01 PM
There are plenty of non-metallic options - glue-and-screw, with the screws removed once the epoxy dries, stitch-and-glue with plastic cable ties instead of wires, trunnels for plank-on-frame construction, plastic staples for cold molding.

And, while we're at it, plastic through-hull fittings, and a plastic prop at the end of a carbon-fiber shaft, powered (someday) by a motor made mostly of plastics and ceramics.

Tom

John Meachen
01-02-2012, 05:58 PM
I'm sticking with bronze -
Even the average humidity here is 40%, let alone if I splash some water around some stressed areas

- I don't see it as a major expense, and as far as resources go: bring it on
- the more people use it, the more people will make it - there seems to be a culture of SS here, and it's not even 316 - and surely it takes more resources to make it than melting copper & silicon

sayla

I don't think I have seen humidity as low as 40% in a long time,76% at the moment and for at least the last three months it has frequently been over 90%.Bronze or monel will outlast most boats but a lot of boats built for a tough life will succumb to physical damage long before the fasteners give out.A good part of the structure in an epoxy encapsulated boat will need fasteners to hold it in place while the epoxy cures and at a later stage some of these fastenings will be in the way of holes for fastenings that attach hardware.Since the hardware will necessarily be held in place with durable fasteners and since we should strive to avoid dissimilar metals coming into contact,its appropriate to use good fastenings.Of course you can glue your hardware in place,omitting the fasteners.

Chan
01-10-2012, 06:24 PM
Sorry for the delay in response.
This is a shellback dinghy I am referring to. The whole thing is held together with epoxy, the bronze screws are all counter sunk and filled with thickened epoxy. I think the plywood laps glued with epoxy and no other fastenings will fail before the scoodge covering the countersunk screws does.

Chan
01-10-2012, 06:44 PM
Perhaps I should have prefaced the comment with the last post.

Mad Scientist
01-10-2012, 08:07 PM
Chan,

I, for one, am glad that you have told us about the type of boat/construction involved.

There was a thread, concerning screw-and-glue boats, dealing with the pros and cons of keeping the metal fasteners in place after the glue had dried. IIRC, no consensus was reached. (Also, IMHO, not surprising!)

My $0.02: Epoxy is stronger than the wood it joins, BUT epoxy is vulnerable to UV damage. So, the joint should be protected. I don't know if resorcinol has a similar vulnerability, or if resorcinol is appropriate for your shellback's glued-lap construction.

Tom

Sayla
01-10-2012, 09:17 PM
My boat is a combination of iron and bronze. It is not encapsulated, which is why she is in fine shape at, now, 83 years of age.

.................................................. ...., but if you are encapsulating it, it is unlikely to last that long, so use whatever you want. I am sticking with bronze, however...

Are you meaning glue built boats, or just encapsulated bits of carvel worked wood?


The whole thing is held together with epoxy, the bronze screws are all counter sunk and filled with thickened epoxy. I think the plywood laps glued with epoxy and no other fastenings will fail before the scoodge covering the countersunk screws does.

Surely the cost isn't really an issue for dinghies - use the bronze to make sure...........and quality epoxy with fillets both sides of the lap joins, and paint over with light colored (white) paint - if ever they fail, which they really shouldn't, then use bronze for that too (perhaps some small stringers)

sayla

Cogeniac
01-10-2012, 09:30 PM
Really any boat that lives in the water. For a small boat that lives out of the water and occasionally gets wet, t really isn't an issue, but for a boat that lives in the water encapsulation will eventually fail, and the resulting water ingress will not saturate the wood, but it will be wet, so it will support rot, and the hull will rot from the inside out.

For some boats this is a fact of life..they are not made to last indefinitely, but for a wood boat fastened to wood frames and living in the water forever, bronze is worth every penny.
S

Chan
01-11-2012, 06:38 PM
Again we are talking about shellback dinghy s.
The entire structure of the boat is dependent upon epoxy.
The design is from the late 1980's and perhaps Joel White was still a bit skeptical of the virtues of epoxy.
There is not 1 joint in this design that is not dependent on glue.
I'm pretty sure the design and build are not new to the forum.
Why Bronze ?